1. Technical Field
Photoresist cleaning solutions are disclosed that prevent undesired ghost pattern formation when cleaning solution is sprayed over photoresist film before or after the pattern is exposed. Methods for pattern formation using the disclosed cleaning solutions are also disclosed.
2. Description of the Related Art
According to current methods for forming photoresist patterns on semiconductor substrates, the underlying layer is formed first on the substrate, and photoresist film is formed over the underlying layer. Then, the photoresist film is exposed to light and developed to obtain photoresist pattern, thereby exposing a part of the underlying layer. When a positive photoresist film is used, the photoresist film of the exposed region is removed using a developing solution.
However, in such a process, there is a problem of undesired pattern formation, i.e. side lobe, by the acid generated at the photosensitizer coating film of an unexposed region due to a ghost image at the undesired region during the exposing procedure. The acid detaches the protecting group of the photosensitizer during baking step and the detached protecting group is removed by the developing solution.